Techniques for indicating time offsets in wireless communications

ABSTRACT

Aspects described herein relate to communicating a demodulation reference signal (DMRS) corresponding to a downlink control channel, buffering, based on receiving the DMRS, samples of a downlink data channel associated with the downlink control channel, and processing, during on a time period indicated based at least in part on a sequence of the DMRS, at least a portion of the samples of the downlink data channel. Another aspect relates to determining, based at least in part on a sequence of the DMRS, a time offset from the downlink control channel to a downlink data channel, and determining, based at least in part on the time offset, a time period based on which to transmit or start processing samples of the downlink data channel.

The present Application for Patent claims priority to Provisional PatentApplication No. 63/023,619, entitled “TECHNIQUES FOR INDICATING TIMEOFFSETS IN WIRELESS COMMUNICATIONS” filed May 12, 2020, which isassigned to the assignee hereof and hereby expressly incorporated byreference herein for all purposes.

BACKGROUND

Aspects of the present disclosure relate generally to wirelesscommunication systems, and more particularly, to timing betweencommunicating control information and corresponding data.

Wireless communication systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be multiple-accesssystems capable of supporting communication with multiple users bysharing the available system resources (e.g., time, frequency, andpower). Examples of such multiple-access systems include code-divisionmultiple access (CDMA) systems, time-division multiple access (TDMA)systems, frequency-division multiple access (FDMA) systems, andorthogonal frequency-division multiple access (OFDMA) systems, andsingle-carrier frequency division multiple access (SC-FDMA) systems.

These multiple access technologies have been adopted in varioustelecommunication standards to provide a common protocol that enablesdifferent wireless devices to communicate on a municipal, national,regional, and even global level. For example, a fifth generation (5G)wireless communications technology (which can be referred to as 5G newradio (5G NR)) is envisaged to expand and support diverse usagescenarios and applications with respect to current mobile networkgenerations. In an aspect, 5G communications technology can include:enhanced mobile broadband addressing human-centric use cases for accessto multimedia content, services and data; ultra-reliable-low latencycommunications (URLLC) with certain specifications for latency andreliability; and massive machine type communications, which can allow avery large number of connected devices and transmission of a relativelylow volume of non-delay-sensitive information.

In some wireless communication technologies, such as fifth generation(5G) new radio (NR), downlink control information (DCI) can be used toindicate a downlink physical downlink shared channel (PDSCH) grant. TheDCI can also include time domain resource assignment (TDRA) informationindicating, based on a lookup table, a slot offset between the physicaldownlink control channel (PDCCH) carrying the DCI to the slot having thePDSCH, a starting symbol, and a length (in number of symbols) of thePDSCH allocation within the PDSCH slot. Thus, the UE receiving thecommunication can decode the DCI, determine the TDRA information, anddetermine a time at which the corresponding PDSCH allocation begins (andthe time length) based on TDRA information.

SUMMARY

The following presents a simplified summary of one or more aspects inorder to provide a basic understanding of such aspects. This summary isnot an extensive overview of all contemplated aspects, and is intendedto neither identify key or critical elements of all aspects nordelineate the scope of any or all aspects. Its sole purpose is topresent some concepts of one or more aspects in a simplified form as aprelude to the more detailed description that is presented later.

According to an aspect, an apparatus for wireless communication isprovided. The apparatus includes a transceiver, a memory configured tostore instructions, and one or more processors coupled with the memoryand the transceiver. The one or more processors are configured toreceive a demodulation reference signal (DMRS) corresponding to adownlink control channel, buffer, based on receiving the DMRS, samplesof a downlink data channel associated with the downlink control channel,and process, during on a time period indicated based at least in part ona sequence of the DMRS, at least a portion of the samples of thedownlink data channel.

In another aspect, an apparatus for wireless communication is providedthat includes a transceiver, a memory configured to store instructions,and one or more processors coupled with the memory and the transceiver.The one or more processors are configured to generate a DMRScorresponding to a downlink control channel to have a DMRS sequenceindicating a time offset from the downlink control channel to a downlinkdata channel, transmit the downlink control channel and the DMRS, andtransmit, based on the time offset, the downlink data channel after thedownlink control channel.

In another aspect, a method of wireless communication is provided. Themethod includes receiving a DMRS corresponding to a downlink controlchannel, buffering, based on receiving the DMRS, samples of a downlinkdata channel associated with the downlink control channel, andprocessing, during on a time period indicated based at least in part ona sequence of the DMRS, at least a portion of the samples of thedownlink data channel.

In another aspect, a method for wireless communication includesgenerating a DMRS corresponding to a downlink control channel to have aDMRS sequence indicating a time offset from the downlink control channelto a downlink data channel, transmitting the downlink control channeland the DMRS, and transmitting, based on the time offset, the downlinkdata channel after the downlink control channel.

To the accomplishment of the foregoing and related ends, the one or moreaspects comprise the features hereinafter fully described andparticularly pointed out in the claims. The following description andthe annexed drawings set forth in detail certain illustrative featuresof the one or more aspects. These features are indicative, however, ofbut a few of the various ways in which the principles of various aspectsmay be employed, and this description is intended to include all suchaspects and their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosed aspects will hereinafter be described in conjunction withthe appended drawings, provided to illustrate and not to limit thedisclosed aspects, wherein like designations denote like elements, andin which:

FIG. 1 illustrates an example of a wireless communication system, inaccordance with various aspects of the present disclosure;

FIG. 2 is a block diagram illustrating an example of a UE, in accordancewith various aspects of the present disclosure;

FIG. 3 is a block diagram illustrating an example of a base station, inaccordance with various aspects of the present disclosure;

FIG. 4 is a flow chart illustrating an example of a method forgenerating a demodulation reference signal (DMRS) to indicate a timeoffset between a downlink control channel and a downlink data channel,in accordance with various aspects of the present disclosure;

FIG. 5 is a flow chart illustrating an example of a method fordetermining, based on a DMRS, a time offset between a downlink controlchannel and a downlink data channel, in accordance with various aspectsof the present disclosure;

FIG. 6 illustrates an example of a resource allocation for determining atime offset based on a DMRS;

FIG. 7 illustrates an example of a resource allocation for indicating acapability for determining a time offset based on a DMRS; and

FIG. 8 is a block diagram illustrating an example of a MIMOcommunication system including a base station and a UE, in accordancewith various aspects of the present disclosure.

DETAILED DESCRIPTION

Various aspects are now described with reference to the drawings. In thefollowing description, for purposes of explanation, numerous specificdetails are set forth in order to provide a thorough understanding ofone or more aspects. It may be evident, however, that such aspect(s) maybe practiced without these specific details.

The described features generally relate to indicating a time offsetbetween control information and corresponding data communications. Insome wireless communication technologies, such as fifth generation (5G)new radio (NR), downlink control information (DCI) can be used toindicate physical downlink shared channel (PDSCH) grants, and the DCIcan include time domain resource assignment (TDRA) information. A lookuptable can be used to map TDRA values into values of k0, S, and L, wherek0 is a slot offset from the slot having the physical downlink controlchannel (PDCCH) that carries the DCI to the slot having the PDSCH, S isthe starting time period indicated as an index of a symbol (e.g.,orthogonal frequency division multiplexing (OFDM) symbol) within theslot of the PDSCH allocation, and L is the length of PDSCH allocationwithin the slot indicated as a number of symbols.

For example, a user equipment (UE) or other device can receive thedownlink communications from a base station or other node via thedownlink control channel (e.g., PDCCH) and corresponding downlink datachannel (e.g., PDSCH). In an example, the base station can configure thelookup table for the UE, or the lookup table can be otherwise specifiedand/or hardcoded in the UE. In either case, the UE can receive DCI fromthe base station over the downlink control channel, determine the TDRAvalue based on decoding the DCI, determine k0, S, and L based ondetermining the values to which the TDRA value maps in the lookup table,and accordingly determine a time offset at which the data channel istransmitted and/or should be received from the base station. Because theUE does not know the TDRA value until it decodes DCI, and as the valuecan be changing based on network scheduling needs, the UE can buffersamples starting from the DCI reception until DCI is decoded just incase PDSCH is present before the UE decodes DCI (e.g., where TDRA valueindicates a slot and symbol offset that is less than UE DCI decodetime).

In higher operating NR bands (e.g., greater than 52.6 gigahertz (GHz)),larger subcarrier spacings (SCSs) are possible to support largerbandwidth with manageable fast Fourier transform (FFT) sizes, such as960 kilohertz (kHz), 1920 kHz, 3840 kHz, etc. Higher SCS can correspondto a smaller OFDM symbol length. In case of the higher SCS (smaller OFDMsymbols), the PDSCH sample buffering may increase, which may also impactUE memory, power, and processing timeline. Therefore, it may bebeneficial for the UE to know the TDRA information (or at least k0)earlier than after DCI decoding to reduce the amount of buffering.Typically, demodulation reference signal (DMRS) sequence detection canoccur earlier than DCI decoding. Thus, in examples described herein,PDCCH DMRS sequence can carry information about the TDRA so that the UEcan determine when to start buffering before DCI decoding is completed.In 5G NR, PDCCH DMRS sequence can be defined per control resource set(CORESET) and can be confined to PDCCH candidates and wideband acrossall PDCCH candidates in the CORESET. PDCCH DMRS sequence can be apseudo-random sequence with initialization that depends at least on OFDMsymbol number within the slot, slot number within a frame, and/orN_(ID), which can be signaled to the UE (or N_(ID) ^(cell) if notsignaled).

In aspects described herein, a DMRS for a control channel can be used tosignal a time offset between the control channel and the correspondingdata channel. For example, the DMRS sequence can map to or otherwiseindicate a k0 value or subset or range of k0 values, TDRA information orsubset or range of TDRA information from which k0, S, and L can bedetermined, etc. In this example, the UE can determine when to startbuffering samples for the data channel based on the DMRS sequencewithout waiting for DCI decoding to determine that start of the datachannel. This can reduce the buffering time for a device, which wouldotherwise start buffering received communications from the time betweenreceiving the control channel and decoding DCI, to the time betweenreceiving the control channel and determining the DMRS sequence. Oncethe DMRS sequence is determined, buffering can occur (e.g., continue)starting at a corresponding k0, and/or any previously buffered samplescan be flushed.

Using the DMRS sequence to determine a starting time for buffering can,in turn, improve UE memory usage, power consumption, processingtimeline, etc. For example, once the device determines the DMRSsequence, it can determine whether to retain buffered data samples forprocessing (e.g., where k0 identified from the DMRS sequence is lessthan or equal to the current time offset from the control channel) orwhether the buffer can be flushed (e.g., where k0 identified from theDMRS sequence is greater than the current time offset from the controlchannel).

The described features will be presented in more detail below withreference to FIGS. 1-8 .

As used in this application, the terms “component,” “module,” “system”and the like are intended to include a computer-related entity, such asbut not limited to hardware, firmware, a combination of hardware andsoftware, software, or software in execution. For example, a componentmay be, but is not limited to being, a process running on a processor, aprocessor, an object, an executable, a thread of execution, a program,and/or a computer. By way of illustration, both an application runningon a computing device and the computing device can be a component. Oneor more components can reside within a process and/or thread ofexecution and a component can be localized on one computer and/ordistributed between two or more computers. In addition, these componentscan execute from various computer readable media having various datastructures stored thereon. The components can communicate by way oflocal and/or remote processes such as in accordance with a signal havingone or more data packets, such as data from one component interactingwith another component in a local system, distributed system, and/oracross a network such as the Internet with other systems by way of thesignal.

Techniques described herein may be used for various wirelesscommunication systems such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, andother systems. The terms “system” and “network” may often be usedinterchangeably. A CDMA system may implement a radio technology such asCDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000covers IS-2000, IS-95, and IS-856 standards. IS-2000 Releases 0 and Aare commonly referred to as CDMA2000 1×, 1×, etc. IS-856 (TIA-856) iscommonly referred to as CDMA2000 1×EV-DO, High Rate Packet Data (HRPD),etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. ATDMA system may implement a radio technology such as Global System forMobile Communications (GSM). An OFDMA system may implement a radiotechnology such as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA),IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDMTM,etc. UTRA and E-UTRA are part of Universal Mobile TelecommunicationSystem (UMTS). 3GPP Long Term Evolution (LTE) and LTE-Advanced (LTE-A)are new releases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE,LTE-A, and GSM are described in documents from an organization named“3rd Generation Partnership Project” (3GPP). CDMA2000 and UMB aredescribed in documents from an organization named “3rd GenerationPartnership Project 2” (3GPP2). The techniques described herein may beused for the systems and radio technologies mentioned above as well asother systems and radio technologies, including cellular (e.g., LTE)communications over a shared radio frequency spectrum band. Thedescription below, however, describes an LTE/LTE-A system for purposesof example, and LTE terminology is used in much of the descriptionbelow, although the techniques are applicable beyond LTE/LTE-Aapplications (e.g., to fifth generation (5G) new radio (NR) networks orother next generation communication systems).

The following description provides examples, and is not limiting of thescope, applicability, or examples set forth in the claims. Changes maybe made in the function and arrangement of elements discussed withoutdeparting from the scope of the disclosure. Various examples may omit,substitute, or add various procedures or components as appropriate. Forinstance, the methods described may be performed in an order differentfrom that described, and various steps may be added, omitted, orcombined. Also, features described with respect to some examples may becombined in other examples.

Various aspects or features will be presented in terms of systems thatcan include a number of devices, components, modules, and the like. Itis to be understood and appreciated that the various systems can includeadditional devices, components, modules, etc. and/or may not include allof the devices, components, modules etc. discussed in connection withthe figures. A combination of these approaches can also be used.

FIG. 1 is a diagram illustrating an example of a wireless communicationssystem and an access network 100. The wireless communications system(also referred to as a wireless wide area network (WWAN)) can includebase stations 102, UEs 104, an Evolved Packet Core (EPC) 160, and/or a5G Core (5GC) 190. The base stations 102 may include macro cells (highpower cellular base station) and/or small cells (low power cellular basestation). The macro cells can include base stations. The small cells caninclude femtocells, picocells, and microcells. In an example, the basestations 102 may also include gNBs 180, as described further herein. Inone example, some nodes of the wireless communication system may have amodem 240 and communicating component 242 for determining a time offsetfrom a control channel to a corresponding data channel, in accordancewith aspects described herein. In addition, some nodes may have a modem340 and scheduling component 342 for configuring a device fordetermining a time offset from a control channel to a corresponding datachannel, in accordance with aspects described herein. Though a UE 104 isshown as having the modem 240 and communicating component 242 and a basestation 102/gNB 180 is shown as having the modem 340 and schedulingcomponent 342, this is one illustrative example, and substantially anynode or type of node may include a modem 240 and communicating component242 and/or a modem 340 and scheduling component 342 for providingcorresponding functionalities described herein.

The base stations 102 configured for 4G LTE (which can collectively bereferred to as Evolved Universal Mobile Telecommunications System (UMTS)Terrestrial Radio Access Network (E-UTRAN)) may interface with the EPC160 through backhaul links 132 (e.g., using an S1 interface). The basestations 102 configured for 5G NR (which can collectively be referred toas Next Generation RAN (NG-RAN)) may interface with 5GC 190 throughbackhaul links 184. In addition to other functions, the base stations102 may perform one or more of the following functions: transfer of userdata, radio channel ciphering and deciphering, integrity protection,header compression, mobility control functions (e.g., handover, dualconnectivity), inter-cell interference coordination, connection setupand release, load balancing, distribution for non-access stratum (NAS)messages, NAS node selection, synchronization, radio access network(RAN) sharing, multimedia broadcast multicast service (MBMS), subscriberand equipment trace, RAN information management (RIM), paging,positioning, and delivery of warning messages. The base stations 102 maycommunicate directly or indirectly (e.g., through the EPC 160 or 5GC190) with each other over backhaul links 134 (e.g., using an X2interface). The backhaul links 134 may be wired or wireless.

The base stations 102 may wirelessly communicate with one or more UEs104. Each of the base stations 102 may provide communication coveragefor a respective geographic coverage area 110. There may be overlappinggeographic coverage areas 110. For example, the small cell 102′ may havea coverage area 110′ that overlaps the coverage area 110 of one or moremacro base stations 102. A network that includes both small cell andmacro cells may be referred to as a heterogeneous network. Aheterogeneous network may also include Home Evolved Node Bs (eNBs)(HeNBs), which may provide service to a restricted group, which can bereferred to as a closed subscriber group (CSG). The communication links120 between the base stations 102 and the UEs 104 may include uplink(UL) (also referred to as reverse link) transmissions from a UE 104 to abase station 102 and/or downlink (DL) (also referred to as forward link)transmissions from a base station 102 to a UE 104. The communicationlinks 120 may use multiple-input and multiple-output (MIMO) antennatechnology, including spatial multiplexing, beamforming, and/or transmitdiversity. The communication links may be through one or more carriers.The base stations 102/UEs 104 may use spectrum up to Y MHz (e.g., 5, 10,15, 20, 100, 400, etc. MHz) bandwidth per carrier allocated in a carrieraggregation of up to a total of Yx MHz (e.g., for x component carriers)used for transmission in the DL and/or the UL direction. The carriersmay or may not be adjacent to each other. Allocation of carriers may beasymmetric with respect to DL and UL (e.g., more or less carriers may beallocated for DL than for UL). The component carriers may include aprimary component carrier and one or more secondary component carriers.A primary component carrier may be referred to as a primary cell (PCell)and a secondary component carrier may be referred to as a secondary cell(SCell).

In another example, certain UEs 104 may communicate with each otherusing device-to-device (D2D) communication link 158. The D2Dcommunication link 158 may use the DL/UL WWAN spectrum. The D2Dcommunication link 158 may use one or more sidelink channels, such as aphysical sidelink broadcast channel (PSBCH), a physical sidelinkdiscovery channel (PSDCH), a physical sidelink shared channel (PSSCH),and a physical sidelink control channel (PSCCH). D2D communication maybe through a variety of wireless D2D communications systems, such as forexample, FlashLinQ, WiMedia, Bluetooth, ZigBee, Wi-Fi based on the IEEE802.11 standard, LTE, or NR.

The wireless communications system may further include a Wi-Fi accesspoint (AP) 150 in communication with Wi-Fi stations (STAs) 152 viacommunication links 154 in a 5 GHz unlicensed frequency spectrum. Whencommunicating in an unlicensed frequency spectrum, the STAs 152/AP 150may perform a clear channel assessment (CCA) prior to communicating inorder to determine whether the channel is available.

The small cell 102′ may operate in a licensed and/or an unlicensedfrequency spectrum. When operating in an unlicensed frequency spectrum,the small cell 102′ may employ NR and use the same 5 GHz unlicensedfrequency spectrum as used by the Wi-Fi AP 150. The small cell 102′,employing NR in an unlicensed frequency spectrum, may boost coverage toand/or increase capacity of the access network.

A base station 102, whether a small cell 102′ or a large cell (e.g.,macro base station), may include an eNB, gNodeB (gNB), or other type ofbase station. Some base stations, such as gNB 180 may operate in atraditional sub 6 GHz spectrum, in millimeter wave (mmW) frequencies,and/or near mmW frequencies in communication with the UE 104. When thegNB 180 operates in mmW or near mmW frequencies, the gNB 180 may bereferred to as an mmW base station. Extremely high frequency (EHF) ispart of the RF in the electromagnetic spectrum. EHF has a range of 30GHz to 300 GHz and a wavelength between 1 millimeter and 10 millimeters.Radio waves in the band may be referred to as a millimeter wave. NearmmW may extend down to a frequency of 3 GHz with a wavelength of 100millimeters. The super high frequency (SHF) band extends between 3 GHzand 30 GHz, also referred to as centimeter wave. Communications usingthe mmW/near mmW radio frequency band has extremely high path loss and ashort range. The mmW base station 180 may utilize beamforming 182 withthe UE 104 to compensate for the extremely high path loss and shortrange. A base station 102 referred to herein can include a gNB 180.

The EPC 160 may include a Mobility Management Entity (MME) 162, otherMMES 164, a Serving Gateway 166, a Multimedia Broadcast MulticastService (MBMS) Gateway 168, a Broadcast Multicast Service Center (BM-SC)170, and a Packet Data Network (PDN) Gateway 172. The MME 162 may be incommunication with a Home Subscriber Server (HSS) 174. The MME 162 isthe control node that processes the signaling between the UEs 104 andthe EPC 160. Generally, the MME 162 provides bearer and connectionmanagement. All user Internet protocol (IP) packets are transferredthrough the Serving Gateway 166, which itself is connected to the PDNGateway 172. The PDN Gateway 172 provides UE IP address allocation aswell as other functions. The PDN Gateway 172 and the BM-SC 170 areconnected to the IP Services 176. The IP Services 176 may include theInternet, an intranet, an IP Multimedia Subsystem (IMS), a PS StreamingService, and/or other IP services. The BM-SC 170 may provide functionsfor MBMS user service provisioning and delivery. The BM-SC 170 may serveas an entry point for content provider MBMS transmission, may be used toauthorize and initiate MBMS Bearer Services within a public land mobilenetwork (PLMN), and may be used to schedule MBMS transmissions. The MBMSGateway 168 may be used to distribute MBMS traffic to the base stations102 belonging to a Multicast Broadcast Single Frequency Network (MBSFN)area broadcasting a particular service, and may be responsible forsession management (start/stop) and for collecting eMBMS relatedcharging information.

The 5GC 190 may include a Access and Mobility Management Function (AMF)192, other AMFs 193, a Session Management Function (SMF) 194, and a UserPlane Function (UPF) 195. The AMF 192 may be in communication with aUnified Data Management (UDM) 196. The AMF 192 can be a control nodethat processes the signaling between the UEs 104 and the 5GC 190.Generally, the AMF 192 can provide QoS flow and session management. UserInternet protocol (IP) packets (e.g., from one or more UEs 104) can betransferred through the UPF 195. The UPF 195 can provide UE IP addressallocation for one or more UEs, as well as other functions. The UPF 195is connected to the IP Services 197. The IP Services 197 may include theInternet, an intranet, an IP Multimedia Subsystem (IMS), a PS StreamingService, and/or other IP services.

The base station may also be referred to as a gNB, Node B, evolved NodeB (eNB), an access point, a base transceiver station, a radio basestation, a radio transceiver, a transceiver function, a basic serviceset (B S S), an extended service set (ESS), a transmit reception point(TRP), or some other suitable terminology. The base station 102 providesan access point to the EPC 160 or 5GC 190 for a UE 104. Examples of UEs104 include a cellular phone, a smart phone, a session initiationprotocol (SIP) phone, a laptop, a personal digital assistant (PDA), asatellite radio, a global positioning system, a multimedia device, avideo device, a digital audio player (e.g., MP3 player), a camera, agame console, a tablet, a smart device, a wearable device, a vehicle, anelectric meter, a gas pump, a large or small kitchen appliance, ahealthcare device, an implant, a sensor/actuator, a display, or anyother similar functioning device. Some of the UEs 104 may be referred toas IoT devices (e.g., parking meter, gas pump, toaster, vehicles, heartmonitor, etc.). IoT UEs may include machine type communication(MTC)/enhanced MTC (eMTC, also referred to as category (CAT)-M, Cat M1)UEs, NB-IoT (also referred to as CAT NB1) UEs, as well as other types ofUEs. In the present disclosure, eMTC and NB-IoT may refer to futuretechnologies that may evolve from or may be based on these technologies.For example, eMTC may include FeMTC (further eMTC), eFeMTC (enhancedfurther eMTC), mMTC (massive MTC), etc., and NB-IoT may include eNB-IoT(enhanced NB-IoT), FeNB-IoT (further enhanced NB-IoT), etc. The UE 104may also be referred to as a station, a mobile station, a subscriberstation, a mobile unit, a subscriber unit, a wireless unit, a remoteunit, a mobile device, a wireless device, a wireless communicationsdevice, a remote device, a mobile subscriber station, an accessterminal, a mobile terminal, a wireless terminal, a remote terminal, ahandset, a user agent, a mobile client, a client, or some other suitableterminology.

In an example, scheduling component 342 can transmit a downlink controlchannel and corresponding reference signal (e.g., DMRS) to a UE forscheduling resources for a corresponding downlink data channel.Scheduling component 342 can generate a sequence for the DMRS to signala time offset between the downlink control channel and the correspondingdownlink data channel. In an example, communicating component 242 canaccordingly receive the DMRS and determine the time offset based on thesequence used for the DMRS. Communicating component 242 can, based onthe time offset, decode the downlink data channel, determine a time forreceiving and/or decoding the downlink data channel, and/or determinewhether to buffer samples for the downlink data channel.

Turning now to FIGS. 2-8 , aspects are depicted with reference to one ormore components and one or more methods that may perform the actions oroperations described herein, where aspects in dashed line may beoptional. Although the operations described below in FIGS. 4-5 arepresented in a particular order and/or as being performed by an examplecomponent, it should be understood that the ordering of the actions andthe components performing the actions may be varied, depending on theimplementation.

Moreover, it should be understood that the following actions, functions,and/or described components may be performed by a specially programmedprocessor, a processor executing specially programmed software orcomputer-readable media, or by any other combination of a hardwarecomponent and/or a software component capable of performing thedescribed actions or functions.

Referring to FIG. 2 , one example of an implementation of UE 104 mayinclude a variety of components, some of which have already beendescribed above and are described further herein, including componentssuch as one or more processors 212 and memory 216 and transceiver 202 incommunication (e.g., coupled, such as communicatively, operationally,electrically, electronically, or otherwise) via one or more buses 244,which may operate in conjunction with modem 240 and/or communicatingcomponent 242 for determining a time offset from a control channel to acorresponding data channel, in accordance with aspects described herein.

In an aspect, the one or more processors 212 can include a modem 240and/or can be part of the modem 240 that uses one or more modemprocessors. Thus, the various functions related to communicatingcomponent 242 may be included in modem 240 and/or processors 212 and, inan aspect, can be executed by a single processor, while in otheraspects, different ones of the functions may be executed by acombination of two or more different processors. For example, in anaspect, the one or more processors 212 may include any one or anycombination of a modem processor, or a baseband processor, or a digitalsignal processor, or a transmit processor, or a receiver processor, or atransceiver processor associated with transceiver 202. In other aspects,some of the features of the one or more processors 212 and/or modem 240associated with communicating component 242 may be performed bytransceiver 202.

Also, memory 216 may be configured to store data used herein and/orlocal versions of applications 275 or communicating component 242 and/orone or more of its subcomponents being executed by at least oneprocessor 212. Memory 216 can include any type of computer-readablemedium usable by a computer or at least one processor 212, such asrandom access memory (RAM), read only memory (ROM), tapes, magneticdiscs, optical discs, volatile memory, non-volatile memory, and anycombination thereof. In an aspect, for example, memory 216 may be anon-transitory computer-readable storage medium that stores one or morecomputer-executable codes defining communicating component 242 and/orone or more of its subcomponents, and/or data associated therewith, whenUE 104 is operating at least one processor 212 to execute communicatingcomponent 242 and/or one or more of its subcomponents.

Transceiver 202 may include at least one receiver 206 and at least onetransmitter 208. Receiver 206 may include hardware, firmware, and/orsoftware code executable by a processor for receiving data, the codecomprising instructions and being stored in a memory (e.g.,computer-readable medium). Receiver 206 may be, for example, a radiofrequency (RF) receiver. In an aspect, receiver 206 may receive signalstransmitted by at least one base station 102. Additionally, receiver 206may process such received signals, and also may obtain measurements ofthe signals, such as, but not limited to, Ec/Io, signal-to-noise ratio(SNR), reference signal received power (RSRP), received signal strengthindicator (RSSI), etc. Transmitter 208 may include hardware, firmware,and/or software code executable by a processor for transmitting data,the code comprising instructions and being stored in a memory (e.g.,computer-readable medium). A suitable example of transmitter 208 mayincluding, but is not limited to, an RF transmitter.

Moreover, in an aspect, UE 104 may include RF front end 288, which mayoperate in communication with one or more antennas 265 and transceiver202 for receiving and transmitting radio transmissions, for example,wireless communications transmitted by at least one base station 102 orwireless transmissions transmitted by UE 104. RF front end 288 may beconnected to one or more antennas 265 and can include one or morelow-noise amplifiers (LNAs) 290, one or more switches 292, one or morepower amplifiers (PAs) 298, and one or more filters 296 for transmittingand receiving RF signals.

In an aspect, LNA 290 can amplify a received signal at a desired outputlevel. In an aspect, each LNA 290 may have a specified minimum andmaximum gain values. In an aspect, RF front end 288 may use one or moreswitches 292 to select a particular LNA 290 and its specified gain valuebased on a desired gain value for a particular application.

Further, for example, one or more PA(s) 298 may be used by RF front end288 to amplify a signal for an RF output at a desired output powerlevel. In an aspect, each PA 298 may have specified minimum and maximumgain values. In an aspect, RF front end 288 may use one or more switches292 to select a particular PA 298 and its specified gain value based ona desired gain value for a particular application.

Also, for example, one or more filters 296 can be used by RF front end288 to filter a received signal to obtain an input RF signal. Similarly,in an aspect, for example, a respective filter 296 can be used to filteran output from a respective PA 298 to produce an output signal fortransmission. In an aspect, each filter 296 can be connected to aspecific LNA 290 and/or PA 298. In an aspect, RF front end 288 can useone or more switches 292 to select a transmit or receive path using aspecified filter 296, LNA 290, and/or PA 298, based on a configurationas specified by transceiver 202 and/or processor 212.

As such, transceiver 202 may be configured to transmit and receivewireless signals through one or more antennas 265 via RF front end 288.In an aspect, transceiver may be tuned to operate at specifiedfrequencies such that UE 104 can communicate with, for example, one ormore base stations 102 or one or more cells associated with one or morebase stations 102. In an aspect, for example, modem 240 can configuretransceiver 202 to operate at a specified frequency and power levelbased on the UE configuration of the UE 104 and the communicationprotocol used by modem 240.

In an aspect, modem 240 can be a multiband-multimode modem, which canprocess digital data and communicate with transceiver 202 such that thedigital data is sent and received using transceiver 202. In an aspect,modem 240 can be multiband and be configured to support multiplefrequency bands for a specific communications protocol. In an aspect,modem 240 can be multimode and be configured to support multipleoperating networks and communications protocols. In an aspect, modem 240can control one or more components of UE 104 (e.g., RF front end 288,transceiver 202) to enable transmission and/or reception of signals fromthe network based on a specified modem configuration. In an aspect, themodem configuration can be based on the mode of the modem and thefrequency band in use. In another aspect, the modem configuration can bebased on UE configuration information associated with UE 104 as providedby the network during cell selection and/or cell reselection.

In an aspect, communicating component 242 can optionally include a timeoffset determining component 252 for determining a time offset betweenthe downlink control channel and a corresponding downlink data channelbased on the DMRS, and/or a sample buffering component 254 for bufferingsamples of the downlink data channel until the time offset can bedetermined, in accordance with aspects described herein.

In an aspect, the processor(s) 212 may correspond to one or more of theprocessors described in connection with the UE in FIG. 8 . Similarly,the memory 216 may correspond to the memory described in connection withthe UE in FIG. 8 .

Referring to FIG. 3 , one example of an implementation of base station102 (e.g., a base station 102 and/or gNB 180, as described above) mayinclude a variety of components, some of which have already beendescribed above, but including components such as one or more processors312 and memory 316 and transceiver 302 in communication (e.g., coupled,such as communicatively, operationally, electrically, electronically, orotherwise) via one or more buses 344, which may operate in conjunctionwith modem 340 and scheduling component 342 for configuring a device fordetermining a time offset from a control channel to a corresponding datachannel, in accordance with aspects described herein.

The transceiver 302, receiver 306, transmitter 308, one or moreprocessors 312, memory 316, applications 375, buses 344, RF front end388, LNAs 390, switches 392, filters 396, PAs 398, and one or moreantennas 365 may be the same as or similar to the correspondingcomponents of UE 104, as described above, but configured or otherwiseprogrammed for base station operations as opposed to UE operations.

In an aspect, scheduling component 342 can optionally include a DMRSgenerating component 352 for generating a DMRS using a sequence selectedto indicate a time offset between a downlink control channel and acorresponding downlink data channel, and a channel transmittingcomponent 354 for transmitting the downlink control channel, downlinkdata channel, DMRSs or other reference signals, etc., in accordance withaspects described herein.

In an aspect, the processor(s) 312 may correspond to one or more of theprocessors described in connection with the base station in FIG. 8 .Similarly, the memory 316 may correspond to the memory described inconnection with the base station in FIG. 8 .

FIG. 4 illustrates a flow chart of an example of a method 400 for usinga DMRS sequence to indicate a time offset between a downlink controlchannel and a downlink data channel, in accordance with aspectsdescribed herein. FIG. 5 illustrates a flow chart of an example of amethod 500 for determining, based on a DMRS sequence, a time offsetbetween a downlink control channel and a downlink data channel, inaccordance with aspects described herein. In an example, a base station102 can perform the functions described in method 400 using one or moreof the components described in FIGS. 1 and 3 . In an example, a UE 104can perform the functions described in method 500 using one or more ofthe components described in FIGS. 1 and 2 . Methods 400 and 500 aredescribed below in conjunction with one another to ease explanation ofthe associated functions and concepts. Methods 400 and 500 are notrequired to be performed in conjunction with one another, and indeed onedevice can be configured to perform method 400 without having acorresponding device that performs method 500 and vice versa, in atleast one example.

In method 400, at Block 402, the base station can generate a DMRScorresponding to a downlink control channel to have a DMRS sequenceindicating a time offset from the downlink control channel to a downlinkdata channel. In an aspect, DMRS generating component 352, e.g., inconjunction with processor(s) 312, memory 316, transceiver 302,scheduling component 342, etc., can generate the DMRS corresponding tothe downlink control channel to have the DMRS sequence indicating thetime offset from the downlink control channel to the downlink datachannel. In one example, the time offset can include a slot offset(e.g., a number of slots) from a slot of the downlink control channel tothe downlink data channel, a symbol offset of a starting symbol withinthe downlink data channel slot at which the downlink data channelbegins, etc. For example, DMRS generating component 352 can generate theDMRS to indicate the time offset, one of a subset of time offset values,a TDRA value, one of a subset of TDRA values, and/or the like. In aspecific example, DMRS generating component 352 can include a value toindicate the time offset as a parameter in an initialization equationused by a sequence generator for generating the DMRS sequence for thedownlink control channel. In this example, DMRS generating component 352can set the value used to indicate the time offset (e.g., whether a slotoffset and/or symbol offset value, indication of one of a subset of slotoffset and/or symbol offset values, TDRA value, indication of one of asubset of TDRA values, etc.), as a parameter in the initializationequation, and can accordingly generate the DMRS sequence using the timeoffset value as a parameter. This can allow a UE or other devicereceiving the DMRS to determine the time offset based on the DMRSsequence, as described.

In one example, in generating the DMRS at Block 402, optionally at Block404, the base station can determine a DMRS sequence that maps to thetime offset or a subset of allowed time offsets. In an aspect, DMRSgenerating component 352, e.g., in conjunction with processor(s) 312,memory 316, transceiver 302, scheduling component 342, etc., candetermine the DMRS sequence that maps to the time offset or a subset ofallowed time offsets. For example, DMRS generating component 352 canselect a DMRS sequence that can be used to indicate the time offset(e.g., where the base station 102 and receiving device can know, store,or otherwise be configured with, the mapping of DMRS sequence, orassociated parameter used to generate the sequence, to time offsetvalue). In another example, DMRS generating component 352 can generatethe DMRS sequence using the time offset value as a parameter, asdescribed. At least where the time offset value is indicated, schedulingcomponent 342 can still indicate the TDRA value in DCI (or otherwiseindicate the starting symbol offset, S, and/or length, L) so thereceiving device can determine the slot offset (e.g., k0) from the DMRSand then determine, based on the DCI, where within the slot the downlinkdata channel begins and/or a length (in symbols) of the downlink datachannel.

In an example, where DMRS generating component 352 selects a time offsetvalue to indicate one of a subset of allowed time offsets, optionally atBlock 406, the base station can transmit a configuration indicating theallowed time offsets. In an aspect, scheduling component 342, e.g., inconjunction with processor(s) 312, memory 316, transceiver 302, etc.,can transmit the configuration indicating the allowed time offsets. Forexample, the configuration may indicate an enumeration of time offsetvalues, and the DMRS can indicate an index into the enumeration. Forexample, the allowed time offsets may include the set of {0,5,10,15}slots. In this example, the time offset value indicated by the DMRS mayinclude {0,1,2,3}, which can respectively refer to a time offset in theset. Moreover, in an example, where the actual time offset is notincluded in the set, DMRS generating component 352 can select one of thevalues in the set that is near the actual time offset (e.g., thesmallest value greater than the actual time offset, the largest valueless than the actual time offset, etc.). Moreover, in an example, thetime offset or subset of allowed time offsets can correspond to a slotoffset value (e.g., k0) and/or a corresponding symbol offset valuewithin the slot.

In one example, in generating the DMRS at Block 402, optionally at Block408, the base station can determine a DMRS sequence that maps to a TDRAvalue or a subset of allowed TDRA values. In an aspect, DMRS generatingcomponent 352, e.g., in conjunction with processor(s) 312, memory 316,transceiver 302, scheduling component 342, etc., can determine the DMRSsequence that maps to the TDRA value or the subset of allowed TDRAvalues, which can correspond to a subset of possible TDRA values thatthe base station 102 may use in subsequent DCI (e.g., and the receivingdevice may assume the base station 102 does not use TDRA values outsideof the subset). For example, DMRS generating component 352 can select aDMRS sequence that can be used to indicate the TDRA value (e.g., wherethe base station 102 and receiving device can know, store, or otherwisebe configured with the mapping of DMRS sequence to TDRA value). Inanother example, DMRS generating component 352 can generate the DMRSsequence using the TDRA value as a parameter, as described.

In an example, where DMRS generating component 352 selects a TDRA valueto indicate one of a subset of allowed TDRA values, optionally at Block410, the base station can transmit a configuration indicating theallowed TDRA values. In an aspect, scheduling component 342, e.g., inconjunction with processor(s) 312, memory 316, transceiver 302, etc.,can transmit the configuration indicating the allowed TDRA values. Forexample, the configuration may indicate an enumeration of TDRA values,and the DMRS can indicate an index into the enumeration. For example,the allowed TDRA values may include a set of values, as described. Inthis example, the TDRA value indicated by the DMRS may include an indexof a TDRA value in the set. Moreover, in an example, where the actualTDRA value is not included in the set, DMRS generating component 352 canselect one of the TDRA values in the set that is near the actual TDRAvalue (e.g., the smallest value greater than the actual TDRA value, thelargest value less than the actual TDRA value, etc.).

In method 400, at Block 412, the base station can transmit the downlinkcontrol channel and the DMRS. In an aspect, channel transmittingcomponent 354, e.g., in conjunction with processor(s) 312, memory 316,transceiver 302, scheduling component 342, etc., can transmit thedownlink control channel and the DMRS. For example, channel transmittingcomponent 354 can transmit the downlink control channel (e.g., PDCCH),which can include DCI for a downlink data channel, and can transmit theDMRS, which can be transmitted in the same symbol or at least the sameslot as the PDCCH. For example, a receiving device can use the DMRS forperforming channel estimation for decoding the PDCCH.

In method 400, at Block 414, the base station can transmit, based on thetime offset, the downlink data channel after the downlink controlchannel. In an aspect, channel transmitting component 354, e.g., inconjunction with processor(s) 312, memory 316, transceiver 302,scheduling component 342, etc., can transmit, based on the time offset,the downlink data channel after the downlink control channel. Forexample, channel transmitting component 354 can transmit the downlinkdata channel (e.g., PDSCH) in resources occurring at a time period thatis the time offset after the downlink control channel (e.g., a number ofslots after the downlink control channel). In addition, for example,channel transmitting component 354 can transmit the downlink datachannel as a number of symbols (e.g., L) within the slot thatcorresponds to a starting symbol (e.g., S), which may be indicated by aTDRA value by the DMRS and/or in the DCI.

In method 500, at Block 502, the UE can receive a DMRS corresponding toa downlink control channel. In an aspect, communicating component 242,e.g., in conjunction with processor(s) 212, memory 216, transceiver 202,etc., can receive the DMRS corresponding to the downlink controlchannel. For example, communicating component 242 can receive the DMRSin a same symbol or at least a same slot as the downlink control channel(e.g., PDCCH), and can use the DMRS for performing channel estimationof, or to otherwise determine one or more parameters for demodulating ordecoding, the downlink control channel. Moreover, as described, the DMRScan have a sequence that indicates the time offset from the downlinkcontrol channel to a downlink data channel, such that the UE 104 candetermine the time offset without having to decode DCI in the downlinkcontrol channel.

In method 500, optionally at Block 504, the UE can determine, based atleast in part on a sequence of the DMRS, a time offset from the downlinkcontrol channel to a downlink data channel. In an aspect, time offsetdetermining component 252, e.g., in conjunction with processor(s) 212,memory 216, transceiver 202, communicating component 242, etc., candetermine, based at least in part on the sequence of the DMRS, the timeoffset from the downlink control channel to the downlink data channel.As described above, DMRS sequence detection can be faster than DCIdecoding, and thus the UE can determine the time offset from the DMRS todetermine whether or when or how long to buffer samples of the downlinkdata channel. In an example, the UE can determine to otherwise decreasea buffering time and/or buffer size used to buffer samples of thedownlink data channel. For example, time offset determining component252 can use multiple hypotheses to detect the timing offset value fromthe DMRS sequence. For example, time offset determining component 252can determine the sequence as received, where the sequence cancorrespond to a sequence of subcarriers or other units of frequency usedto transmit the DMRS in a symbol or other time division. Given multiplehypotheses for the time offset, and known values of OFDM symbol numberwithin a slot, or slot number within a frame, N_(ID) (or N_(ID)^(cell)), as described above, time offset determining component 252 canattempt to determine the time offset based on the hypotheses bydetermining a sequence for at least one or more of the hypotheses, andcomparing the determined sequence(s) to the sequence of the receivedDMRS.

In an example, in determining the time offset at Block 504, optionallyat Block 506, the UE can determine a mapping between the sequence of theDMRS and the time offset or a subset of allowed time offsets. In anaspect, time offset determining component 252, e.g., in conjunction withprocessor(s) 212, memory 216, transceiver 202, communicating component242, etc., can determine the mapping between the sequence of the DMRSand the time offset or the subset of allowed time offsets. For example,time offset determining component 252 can determine the time offset thatis indicated by or maps to the DMRS sequence (e.g., where the basestation 102 and receiving device can know the mapping of DMRS sequenceto time offset value). In one example, base station 102 can configurethe UE 104 with the mapping (e.g., radio resource control (RRC)signaling, remaining minimum system information (RMSI), or otherconfiguration signaling). In another example, time offset determiningcomponent 252 can determine the time offset value by testing differenthypotheses for the time offset value and corresponding generated DMRSsequences, as described. At least where the time offset value isdetermined, time offset determining component 252 can still determinethe TDRA value based on decoding the DCI (or otherwise determine thestarting symbol offset, S, and/or length, L) so it can determine wherewithin the slot the downlink data channel begins and/or a length (insymbols) of the downlink data channel.

In an example, where time offset determining component 252 determines atime offset value as one of a subset of allowed time offsets, optionallyat Block 508, the UE can receive a configuration indicating the allowedtime offsets. In an aspect, communicating component 242, e.g., inconjunction with processor(s) 212, memory 216, transceiver 202, etc.,can receive (e.g., from the base station 102 in RRC signaling, RMSI, orother configuration signaling), the configuration indicating the allowedtime offsets. For example, the configuration may indicate an enumerationof time offset values, and the DMRS can indicate an index into theenumeration. For example, the allowed time offsets may include the setof {0,5,10,15} slots. In this example, the time offset value indicatedby the DMRS may include {0,1,2,3}, which can respectively refer to atime offset in the set. Moreover, in an example, where the actual timeoffset is not included in the set, time offset determining component 252can determine one of the values in the set that is near the actual timeoffset (e.g., the smallest value greater than the actual time offset,the largest value less than the actual time offset, etc.). Moreover, inan example, the time offset or subset of allowed time offsets cancorrespond to a slot offset value (e.g., k0) and/or a correspondingsymbol offset value within the slot.

In one example, in determine the time offset at Block 504, optionally atBlock 510, the UE can determine a mapping between the sequence of theDMRS and a TDRA value or a subset of allowed TDRA values In an aspect,time offset determining component 252, e.g., in conjunction withprocessor(s) 212, memory 216, transceiver 202, communicating component242, etc., can determine the mapping between the sequence of the DMRSand the TDRA value or the subset of allowed TDRA values, which cancorrespond to a subset of possible TDRA values that the base station 102may use in subsequent DCI (e.g., and the UE 104 may assume the basestation 102 does not use TDRA values outside of the subset). Forexample, time offset determining component 252 can determine the TDRAvalue that is indicated by or maps to the DMRS sequence (e.g., where thebase station 102 and receiving device can know, store, or otherwise beconfigured with the mapping of DMRS sequence to TDRA value). In anotherexample, time offset determining component 252 can determine the TDRAvalue by testing different hypotheses for the TDRA value andcorresponding generated DMRS sequences, as described.

In an example, where time offset determining component 252 determines aTDRA value as one of a subset of allowed TDRA values, optionally atBlock 512, the UE can receive a configuration indicating the allowedTDRA values. In an aspect, communicating component 242, e.g., inconjunction with processor(s) 212, memory 216, transceiver 202, etc.,can receive the configuration indicating the allowed TDRA values. Forexample, communicating component 242 can receive the configuration fromthe base station 102 or other node in RRC signaling, RMSI, or otherconfiguration signaling. For example, the configuration may indicate anenumeration of TDRA values, and the DMRS can indicate an index into theenumeration. For example, the allowed TDRA values may include a set ofvalues, as described. In this example, the TDRA value indicated by theDMRS may include an index of a TDRA value in the set. Moreover, in anexample, where the actual TDRA value is not included in the set, timeoffset determining component 252 can determine one of the TDRA values inthe set that is near the actual TDRA value (e.g., the smallest valuegreater than the actual TDRA value, the largest value less than theactual TDRA value, etc.).

In method 500, optionally at Block 514, the UE can buffer, based onreceiving the DMRS, samples of a downlink data channel associated withthe downlink control channel. In an aspect, sample buffering component254, e.g., in conjunction with processor(s) 212, memory 216, transceiver202, communicating component 242, etc., can buffer, based on receivingthe DMRS, samples of the downlink data channel associated with thedownlink control channel. For example, sample buffering component 254can buffer the samples by storing the received samples, and/orrepresentative data or information, in a memory 216 or other storage forpossible subsequent processing. In an example, sample bufferingcomponent 254 can store time information for the samples for subsequentdetermination of which samples to process, as described further herein.Moreover, in an example, sample buffering component 254 can beginbuffering samples of the downlink data channel once the downlink controlchannel is detected and/or received, etc. In addition, as describedabove and further herein, sample buffering component 254 can determinehow to buffer samples based on the DMRS, such as starting bufferingbased on receiving the DMRS or the downlink control channel, pausingbuffering and/or flushing the buffer where the DMRS indicates a slotoffset subsequent in time to a current slot, begin or continue bufferingat the slot offset until DCI can be decoded, etc.

In method 500, optionally at Block 516, the UE can determine, based atleast in part on the time offset, a time period based on which to startprocessing samples of the downlink data channel. In an aspect,communicating component 242, e.g., in conjunction with processor(s) 212,memory 216, transceiver 202, etc., can determine, based at least in parton the time offset, the time period based on which to start processingsamples of the downlink data channel (e.g., from the buffer orotherwise). For example, where the time offset indicates a slot offset,communicating component 242 can determine that the downlink data channel(e.g., PDSCH) corresponding to the uplink control channel (e.g., PDCCH)starts in a slot that is a number of slots, indicated by the slotoffset, from the uplink control channel. In this example, communicatingcomponent 242 may determine a starting symbol within the slot and/or alength of the downlink data channel (e.g., in symbols) based on otherparameters, based on the TDRA value decoded from DCI, etc. In anotherexample, where the time offset indicates a TDRA value, communicatingcomponent 242 can determine that the downlink data channel (e.g., PDSCH)corresponding to the uplink control channel (e.g., PDCCH) starts in aslot that is a number of slots, indicated by the slot offset k0, fromthe uplink control channel. In this example, communicating component 242can determine the slot offset k0 specified for the TDRA value in alookup table, and/or can determine the starting symbol, S, the length,L, etc.

In method 500, optionally at Block 518, the UE can process samples ofthe downlink data channel corresponding to the time period. In anaspect, communicating component 242, e.g., in conjunction withprocessor(s) 212, memory 216, transceiver 202, etc., can process samplesof the downlink data channel (e.g., PDSCH) corresponding to the timeperiod. For example, communicating component 242 can process samplesreceived in the slot indicated by the slot offset, at the indicatedstarting symbol within the slot, for an indicated length, etc., asdescribed. In an example, sample buffering component 254 can buffersamples of the downlink data channel that are received following thedownlink control channel and at least until the DMRS is processed and/orbased on determining a starting slot or symbol from the DMRS, asdescribed. Where the time offset is less than the time it takes toprocess the DMRS, for example, at least some of the buffered samples maybe processed.

As described above, the early indication of the time offset can be usedto allow the UE 104 to determine when and/or whether to buffer samples,which can improve UE performance. Thus, sample buffering component 254can begin buffering samples of the downlink data channel after receivingthe downlink control channel and at least until the DMRS is received orthe time offset is accordingly determined from the DMRS.

In method 500, optionally at Block 520, the UE can determine, based atleast in part on the time offset, at least one of whether to continuebuffering samples of the downlink data channel or whether to flush thebuffered samples of the downlink data channel. In an aspect, samplebuffering component 254, e.g., in conjunction with processor(s) 212,memory 216, transceiver 202, communicating component 242, etc., candetermine, based at least in part on the time offset, at least one ofwhether to continue buffering samples of the downlink data channel orwhether to flush the buffered samples of the downlink data channel.

For example, where the time offset determined from the DMRS is less thana current time offset from the downlink control channel, samplebuffering component 254 can determine to continue buffering samples atleast for a period of time corresponding to the determined time offsetfrom the downlink control channel and possibly for the length of thedownlink data channel (if known, e.g., where the DMRS indicates the TDRAvalue). In another example, sample buffering component 254 can continuebuffering the samples until DCI is decoded and other parameters relatedto the downlink data channel can be accordingly determined.

In another example, where the time offset determined from the DMRS isgreater than a current time offset from the downlink control channel,sample buffering component 254 can determine to flush the bufferedsamples at least for a time period from the beginning of the downlinkcontrol channel until the determined time offset (or until DCI isdecoded), and/or can determine to stop buffering samples until the timecorresponding to the time offset from the downlink control channel. Inaddition, for example, where the determined time offset is greater thana current time offset from the downlink control channel, samplebuffering component 254 can also determine to start buffering samples ofthe downlink data channel from the time corresponding to the time offsetfrom the downlink control channel and for the length of the downlinkdata channel (if known, e.g., where the DMRS indicates the TDRA value,or until DCI is decoded and other parameters related to the downlinkdata channel can be accordingly determined. Where sample bufferingcomponent 254 determines to flush buffered samples, optionally at Block522, the UE can flush the buffered samples. In an aspect, samplebuffering component 254, e.g., in conjunction with processor(s) 212,memory 216, transceiver 202, communicating component 242, etc., canflush the buffered samples, which can include removing at least aportion of buffered samples from a memory (e.g., memory 216). An exampleis shown in FIG. 6 .

FIG. 6 illustrates an example of a resource allocation 600 including aCORESET and PDCCH/DCI 602 that is initially received and indicatescontrol information for PDSCH 604, which is k0 slot offset from CORESETand PDCCH/DCI 602. A DMRS can also be transmitted with CORESET andPDCCH/DCI 602 and can indicate the time offset (e.g., k0, or a valuefrom which k0 can be determined). The UE can accordingly process theDMRS and determine the time offset in time period 606 to achieve abuffer savings 608 over the time it takes for the UE to decode DCI 610.

For example, it may still take time for the UE to detect the k0/TDRAvalue from the PDCCH DMRS, so the UE can still buffer samples until k0is detected from the DMRS, as described above. In one example, to reducethe buffering even further, the UE can send capability informationrelated to whether the UE can support the early detecting of the timeoffset (e.g., based on DMRS). In method 500, optionally at Block 524,the UE can transmit a capability indicating a supported time fordetermining time offsets based on DMRS sequences. In an aspect,communicating component 242, e.g., in conjunction with processor(s) 212,memory 216, transceiver 202, etc., can transmit the capabilityindicating the supported time for determining time offsets based on DMRSsequences. For example, the capability can indicate the ability of theUE 104 to determine time offset based on DMRS or parameters related tohow long it takes the UE to determine time offset from DMRS. In anexample, the capability can be based on (and/or specified for each of) anumber of PDCCH candidates, a number of time offset hypotheses supportedby the UE in processing the DMRS to determine the time offset, acorresponding SCS, etc., which can allow the base station 102 todetermine a time for the UE 104 to ascertain the time offset from theDMRS. The base station 102 can, in one example, set the time offset tobe at least the supported time indicated in the capability. In anexample, communicating component 242 can transmit the capability basedon a request from the base station 102, along with other capabilityinformation for the UE 104, etc., which may be via RRC or other higherlayer signaling.

In method 400, optionally at Block 416, the base station can receive acapability indicating a supported time for determining time offsetsbased on DMRS sequences. In an aspect, scheduling component 342, e.g.,in conjunction with processor(s) 312, memory 316, transceiver 302, etc.,can receive (e.g., from the UE 104) the capability indicating thesupported time for determining time offsets based on DMRS sequences. Asdescribed, the capability may be specified for a number of PDCCHcandidates, a number of time offset hypotheses, a corresponding SCS,etc., and scheduling component 342 can determine the supported timebased on the number of PDCCH candidates, the number of time offsethypotheses configured, the SCS, etc. In this example, schedulingcomponent 342 can determine a time offset between the downlink controlchannel and the downlink data channel that is at least the supportedtime (e.g., and in generating the DMRS to indicate the time offset atBlock 402, DMRS generating component 352 can specify the time offsetthat is at least the supported time). Thus, for example, the network canensure it does not schedule TDRA that is smaller than the UE capability.

In addition, for example, in method 400, optionally at Block 418, thebase station can transmit an indication that the time offset is not lessthan the supported time. In an aspect, scheduling component 342, e.g.,in conjunction with processor(s) 312, memory 316, transceiver 302, etc.,can transmit the indication that the time offset is not less than thesupported time. In an example, scheduling component 342 can transmit theindication for all time offsets for the UE 104 (e.g., in RRC or otherhigher layer signaling), or for each time offset (e.g., in controlsignaling), so the UE 104 can determine whether the base station 102sets the time offsets in consideration of the supported time for the UE104.

In method 500, optionally at Block 526, the UE can receive an indicationthat the time offset is not less than the supported time. In an aspect,communicating component 242, e.g., in conjunction with processor(s) 212,memory 216, transceiver 202, etc., can receive the indication (e.g.,from the base station 102) that the time offset is not less than thesupported time indicated by the UE 104. Based on this indication, forexample, time offset determining component 252 can decide to determinethe time offset from the DMRS, and sample buffering component 254 maynot need to buffer samples, or may only buffer samples from the time ofreceiving the DMRS until decoding DCI to determine other parameters forreceiving the downlink data channel. If the indication is not received(and/or the capability is not indicated), however, sample bufferingcomponent 254 can start PDSCH sample buffering from the PDCCH DCIreception. An example is shown in FIG. 7 .

FIG. 7 illustrates an example of a resource allocation 700 including aCORESET and PDCCH/DCI 702 that is initially received and indicatescontrol information for PDSCH 704, which is k0 slot offset from CORESETand PDCCH/DCI 702. A DMRS can also be transmitted with CORESET andPDCCH/DCI 702 and can indicate the time offset (e.g., k0, or a valuefrom which k0 can be determined). Based on an indicated capability ofthe UE to detect time offset from DMRS within a time period 706, thenetwork can refrain from scheduling the PDSCH before the end of timeperiod 706 (and may indicate this to the UE). The UE can accordinglyrefrain from buffering until this point as well, and can process theDMRS and determine the time offset after time period 706. Thus, the UEcan achieve a buffer savings 708 over the time it takes for the UE todecode DCI 710.

FIG. 8 is a block diagram of a MIMO communication system 800 including abase station 102 and a UE 104. The MIMO communication system 800 mayillustrate aspects of the wireless communication access network 100described with reference to FIG. 1 . The base station 102 may be anexample of aspects of the base station 102 described with reference toFIG. 1 . The base station 102 may be equipped with antennas 834 and 835,and the UE 104 may be equipped with antennas 852 and 853. In the MIMOcommunication system 800, the base station 102 may be able to send dataover multiple communication links at the same time. Each communicationlink may be called a “layer” and the “rank” of the communication linkmay indicate the number of layers used for communication. For example,in a 2×2 MIMO communication system where base station 102 transmits two“layers,” the rank of the communication link between the base station102 and the UE 104 is two.

At the base station 102, a transmit (Tx) processor 820 may receive datafrom a data source. The transmit processor 820 may process the data. Thetransmit processor 820 may also generate control symbols or referencesymbols. A transmit MIMO processor 830 may perform spatial processing(e.g., precoding) on data symbols, control symbols, or referencesymbols, if applicable, and may provide output symbol streams to thetransmit modulator/demodulators 832 and 833. Each modulator/demodulator832 through 833 may process a respective output symbol stream (e.g., forOFDM, etc.) to obtain an output sample stream. Eachmodulator/demodulator 832 through 833 may further process (e.g., convertto analog, amplify, filter, and upconvert) the output sample stream toobtain a DL signal. In one example, DL signals frommodulator/demodulators 832 and 833 may be transmitted via the antennas834 and 835, respectively.

The UE 104 may be an example of aspects of the UEs 104 described withreference to FIGS. 1-2 . At the UE 104, the UE antennas 852 and 853 mayreceive the DL signals from the base station 102 and may provide thereceived signals to the modulator/demodulators 854 and 855,respectively. Each modulator/demodulator 854 through 855 may condition(e.g., filter, amplify, downconvert, and digitize) a respective receivedsignal to obtain input samples. Each modulator/demodulator 854 through855 may further process the input samples (e.g., for OFDM, etc.) toobtain received symbols. A MIMO detector 856 may obtain received symbolsfrom the modulator/demodulators 854 and 855, perform MIMO detection onthe received symbols, if applicable, and provide detected symbols. Areceive (Rx) processor 858 may process (e.g., demodulate, deinterleave,and decode) the detected symbols, providing decoded data for the UE 104to a data output, and provide decoded control information to a processor880, or memory 882.

The processor 880 may in some cases execute stored instructions toinstantiate a communicating component 242 (see e.g., FIGS. 1 and 2 ).

On the uplink (UL), at the UE 104, a transmit processor 864 may receiveand process data from a data source. The transmit processor 864 may alsogenerate reference symbols for a reference signal. The symbols from thetransmit processor 864 may be precoded by a transmit MIMO processor 866if applicable, further processed by the modulator/demodulators 854 and855 (e.g., for SC-FDMA, etc.), and be transmitted to the base station102 in accordance with the communication parameters received from thebase station 102. At the base station 102, the UL signals from the UE104 may be received by the antennas 834 and 835, processed by themodulator/demodulators 832 and 833, detected by a MIMO detector 836 ifapplicable, and further processed by a receive processor 838. Thereceive processor 838 may provide decoded data to a data output and tothe processor 840 or memory 842.

The processor 840 may in some cases execute stored instructions toinstantiate a scheduling component 342 (see e.g., FIGS. 1 and 3 ).

The components of the UE 104 may, individually or collectively, beimplemented with one or more ASICs adapted to perform some or all of theapplicable functions in hardware. Each of the noted modules may be ameans for performing one or more functions related to operation of theMIMO communication system 800. Similarly, the components of the basestation 102 may, individually or collectively, be implemented with oneor more application specific integrated circuits (ASICs) adapted toperform some or all of the applicable functions in hardware. Each of thenoted components may be a means for performing one or more functionsrelated to operation of the MIMO communication system 800.

The following aspects are illustrative only and aspects thereof may becombined with aspects of other embodiments or teaching described herein,without limitation.

Aspect 1 is a method for wireless communication including receiving aDMRS corresponding to a downlink control channel, determining, based atleast in part on a sequence of the DMRS, a time offset from the downlinkcontrol channel to a downlink data channel, and determining, based atleast in part on the time offset, a time period based on which to startprocessing samples of the downlink data channel.

In Aspect 2, the method of Aspect 1 includes buffering samples of thedownlink data channel based on receiving the downlink control channelcorresponding to the downlink data channel, and determining, based atleast in part on the time offset, at least one of whether to continuethe buffering samples of the downlink data channel or whether to flushbuffered samples of the downlink data channel.

In Aspect 3, the method of Aspect 2 includes where determining the timeperiod includes determining to process at least a portion of thebuffered samples of the downlink data channel.

In Aspect 4, the method of any of Aspects 1 to 3 includes wheredetermining the time offset includes determining a mapping between thesequence of the DMRS and the time offset.

In Aspect 5, the method of any of Aspects 1 to 4 includes wheredetermining the time offset includes determining a mapping between thesequence of the DMRS and a subset of allowed time offsets.

In Aspect 6, the method of Aspect 5 includes receiving a configurationindicating the allowed time offsets.

In Aspect 7, the method of any of Aspects 1 to 6 includes wheredetermining the time offset includes determining a mapping between thesequence of the DMRS and a TDRA value, and further comprisingdetermining, from a lookup table, the time offset based at least in parton a TDRA time offset value indicated for the TDRA value.

In Aspect 8, the method of any of Aspects 1 to 7 includes wheredetermining the time offset includes determining a mapping between thesequence of the DMRS and a subset of allowed TDRA values.

In Aspect 9, the method of Aspect 8 includes receiving a configurationindicating the allowed TDRA values.

In Aspect 10, the method of any of Aspects 1 to 9 includes transmittinga capability indicating a supported time for determining time offsetsbased on DMRS sequences.

In Aspect 11, the method of Aspect 10 includes where the capability isindicated for at least one of a number of control channel candidates, anumber of time offset or TDRA value hypotheses, or a subcarrier spacing.

In Aspect 12, the method of any of Aspects 10 or 11 includes receivingan indication that the time offset is not less than the supported time,where determining, based at least in part on the sequence of the DMRS,the time offset is based at least in part on receiving the indication.

Aspect 13 is a method for wireless communication including generating aDMRS corresponding to a downlink control channel to have a DMRS sequenceindicating a time offset from the downlink control channel to a downlinkdata channel, transmitting the downlink control channel and the DMRS,and transmitting, based on the time offset, the downlink data channelafter the downlink control channel.

In Aspect 14, the method of Aspect 13 includes where generating the DMRSincludes determining the DMRS sequence that maps to the time offset.

In Aspect 15, the method of any of Aspects 13 or 14 includes wheregenerating the DMRS includes determining the DMRS sequence that maps toa subset of allowed time offsets that includes the time offset.

In Aspect 16, the method of Aspect 15 includes transmitting aconfiguration indicating the allowed time offsets.

In Aspect 17, the method of any of Aspects 13 to 16 includes wheregenerating the DMRS includes determining the DMRS sequence that maps toa TDRA value related to the time offset.

In Aspect 18, the method of any of Aspects 13 to 17 includes wheregenerating the DMRS includes determining the DMRS sequence that maps toa subset of allowed TDRA values that includes a TDRA value related tothe time offset.

In Aspect 19, the method of Aspect 18 includes transmitting aconfiguration indicating the allowed TDRA values.

In Aspect 20, the method of any of Aspects 13 to 19 includes receiving acapability indicating a supported time for determining time offsetsbased on DMRS sequences, where generating the DMRS includes selecting aDMRS sequence based on determining that the time offset is within thesupported time.

In Aspect 21, the method of Aspect 20 includes where the capability isindicated for at least one of a number of control channel candidates, anumber of time offset or TDRA value hypotheses, or a subcarrier spacing.

In Aspect 22, the method of any of Aspects 20 or 21 includestransmitting an indication that the time offset is not less than thesupported time.

Aspect 23 is a method for wireless communication including receiving aDMRS corresponding to a downlink control channel, buffering, based onreceiving the DMRS, samples of a downlink data channel associated withthe downlink control channel, and processing, during on a time periodindicated based at least in part on a sequence of the DMRS, at least aportion of the samples of the downlink data channel.

In Aspect 24, the method of Aspect 23 includes where the sequence of theDMRS indicates a time offset from the downlink control channel to thedownlink data channel, and wherein processing at least the portion ofthe samples during on the time period is based on the time offset.

In Aspect 25, the method of any of Aspects 23 or 24, includes, based atleast in part on the time offset, one of continuing the bufferingsamples of the downlink data channel or flushing buffered samples of thedownlink data channel.

In Aspect 26, the method of any of Aspects 23 to 25 includes determiningthe time offset based on a mapping between the sequence of the DMRS andthe time offset.

In Aspect 27, the method of any of Aspects 23 to 26 includes determiningthe time offset based on a mapping between the sequence of the DMRS anda subset of allowed time offsets.

In Aspect 28, the method of Aspect 27 includes receiving a configurationindicating the allowed time offsets.

In Aspect 29, the method of any of Aspects 23 to 28 includes determiningthe time offset based on a mapping between the sequence of the DMRS anda TDRA value, and further comprising determining, from a lookup table,the time offset based at least in part on a TDRA time offset valueindicated for the TDRA value.

In Aspect 30, the method of any of Aspects 23 to 29 includes determiningthe time offset based on a mapping between the sequence of the DMRS anda subset of allowed TDRA values.

In Aspect 31, the method of Aspect 30 includes receiving a configurationindicating the allowed TDRA values.

In Aspect 32, the method of any of Aspects 23 to 31 includestransmitting a capability indicating a supported time for determiningtime offsets based on DMRS sequences.

In Aspect 33, the method of Aspect 32 includes where the capability isindicated for at least one of a number of control channel candidates, anumber of time offset or TDRA value hypotheses, or a subcarrier spacing.

In Aspect 34, the method of Aspect 32 includes receiving an indicationthat the time offset is not less than the supported time, anddetermining, based at least in part on the sequence of the DMRS, thetime offset based at least in part on receiving the indication.

Aspect 35 is an apparatus for wireless communication including atransceiver, a memory configured to store instructions, and one or moreprocessors communicatively coupled with the memory and the transceiver,where the one or more processors are configured to perform one or moreof the methods of any of Aspects 1 to 34.

Aspect 36 is an apparatus for wireless communication including means forperforming one or more of the methods of any of Aspects 1 to 34.

Aspect 37 is a computer-readable medium including code executable by oneor more processors for wireless communications, the code including codefor performing one or more of the methods of any of Aspects 1 to 34.

The above detailed description set forth above in connection with theappended drawings describes examples and does not represent the onlyexamples that may be implemented or that are within the scope of theclaims. The term “example,” when used in this description, means“serving as an example, instance, or illustration,” and not “preferred”or “advantageous over other examples.” The detailed description includesspecific details for the purpose of providing an understanding of thedescribed techniques. These techniques, however, may be practicedwithout these specific details. In some instances, well-known structuresand apparatuses are shown in block diagram form in order to avoidobscuring the concepts of the described examples.

Information and signals may be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that may bereferenced throughout the above description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, computer-executable code or instructionsstored on a computer-readable medium, or any combination thereof.

The various illustrative blocks and components described in connectionwith the disclosure herein may be implemented or performed with aspecially programmed device, such as but not limited to a processor, adigital signal processor (DSP), an ASIC, a field programmable gate array(FPGA) or other programmable logic device, a discrete gate or transistorlogic, a discrete hardware component, or any combination thereofdesigned to perform the functions described herein. A speciallyprogrammed processor may be a microprocessor, but in the alternative,the processor may be any conventional processor, controller,microcontroller, or state machine. A specially programmed processor mayalso be implemented as a combination of computing devices, e.g., acombination of a DSP and a microprocessor, multiple microprocessors, oneor more microprocessors in conjunction with a DSP core, or any othersuch configuration. The processors can be coupled (e.g.,communicatively, operationally, electrically, electronically, orotherwise) to memory.

The functions described herein may be implemented in hardware, software(e.g., executed by a processor), or any combination thereof. Softwareshall be construed broadly to mean instructions, instruction sets, code,code segments, program code, programs, subprograms, software modules,applications, software applications, software packages, routines,subroutines, objects, executables, threads of execution, procedures, orfunctions, whether referred to as software, firmware, middleware,microcode, hardware description language, or otherwise. If implementedin software executed by a processor, the functions may be stored on ortransmitted over as one or more instructions or code on acomputer-readable medium. If implemented in software (e.g., executed bya processor), the functions may be stored on or transmitted over as oneor more instructions or code on a non-transitory computer-readablemedium. Other examples and implementations are within the scope andspirit of the disclosure and appended claims. For example, due to thenature of software, functions described above can be implemented usingsoftware (e.g., executed by a specially programmed processor), hardware,hardwiring, or combinations of any of these. Features implementingfunctions may also be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations. Also, as used herein, including in theclaims, “or” (e.g., as used in a list of items prefaced by “at least oneof”) indicates a disjunctive list such that, for example, a list of “atleast one of A, B, or C” means A or B or C or AB or AC or BC or ABC(i.e., A and B and C). Also, as used herein, the phrase “based on” shallnot be construed as a reference to a closed set of conditions. Forexample, an example step that is described as “based on condition A” maybe based on both a condition A and a condition B without departing fromthe scope of the present disclosure. In other words, as used herein, thephrase “based on” shall be construed in the same manner as the phrase“based at least in part on.” As used herein, the term “and/or,” whenused in a list of two or more items, means that any one of the listeditems can be employed by itself, or any combination of two or more ofthe listed items can be employed. For example, if a composition isdescribed as containing components A, B, and/or C, the composition cancontain A alone; B alone; C alone; A and B in combination; A and C incombination; B and C in combination; or A, B, and C in combination.

Computer-readable media includes both computer storage media andcommunication media including any medium that facilitates transfer of acomputer program from one place to another. A storage medium may be anyavailable medium that can be accessed by a general purpose or specialpurpose computer. By way of example, and not limitation,computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or otheroptical disk storage, magnetic disk storage or other magnetic storagedevices, or any other medium that can be used to carry or store desiredprogram code means in the form of instructions or data structures andthat can be accessed by a general-purpose or special-purpose computer,or a general-purpose or special-purpose processor. Also, any connectionis properly termed a computer-readable medium. For example, if thesoftware is transmitted from a website, server, or other remote sourceusing a coaxial cable, fiber optic cable, twisted pair, digitalsubscriber line (DSL), or wireless technologies such as infrared, radio,and microwave, then the coaxial cable, fiber optic cable, twisted pair,DSL, or wireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,include compact disc (CD), laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

The previous description of the disclosure is provided to enable aperson skilled in the art to make or use the disclosure. Variousmodifications to the disclosure will be readily apparent to thoseskilled in the art, and the common principles defined herein may beapplied to other variations without departing from the spirit or scopeof the disclosure. Furthermore, although elements of the describedaspects and/or embodiments may be described or claimed in the singular,the plural is contemplated unless limitation to the singular isexplicitly stated. Additionally, all or a portion of any aspect and/orembodiment may be utilized with all or a portion of any other aspectand/or embodiment, unless stated otherwise. Thus, the disclosure is notto be limited to the examples and designs described herein but is to beaccorded the widest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. An apparatus for wireless communication,comprising: a transceiver; a memory configured to store instructions;and one or more processors coupled with the memory and the transceiver,wherein the one or more processors are configured to: receive ademodulation reference signal (DMRS) that can be used to perform channelestimation for a downlink control channel, wherein a sequence of theDMRS indicates a time offset from the downlink control channel to adownlink data channel; buffer, based on receiving the DMRS and until atime at which the time offset is determined from the sequence of theDMRS, samples of the downlink data channel associated with the downlinkcontrol channel; flush buffered samples of the downlink data channelwhere the time offset from the downlink control channel is after thetime at which the time offset is determined from the sequence of theDMRS; and process at least a portion of the buffered samples of thedownlink data channel where the time offset from the downlink controlchannel is before the time at which the time offset is determined fromthe sequence of the DMRS.
 2. The apparatus of claim 1, wherein the oneor more processors are further configured to determine the time offsetbased on a mapping between the sequence of the DMRS and the time offset.3. The apparatus of claim 1, wherein the one or more processors arefurther configured to determine the time offset based on a mappingbetween the sequence of the DMRS and a subset of allowed time offsets.4. The apparatus of claim 3, wherein the one or more processors arefurther configured to receive a configuration indicating the allowedtime offsets.
 5. The apparatus of claim 1, wherein the one or moreprocessors are further configured to determine the time offset based ona mapping between the sequence of the DMRS and a time domain resourceassignment (TDRA) value, and determine, from a lookup table, the timeoffset based at least in part on a TDRA time offset value indicated forthe TDRA value.
 6. The apparatus of claim 1, wherein the one or moreprocessors are further configured to determine the time offset based ona mapping between the sequence of the DMRS and a subset of allowed timedomain resource assignment (TDRA) values.
 7. The apparatus of claim 6,wherein the one or more processors are further configured to receive aconfiguration indicating the allowed TDRA values.
 8. The apparatus ofclaim 1, wherein the one or more processors are further configured totransmit a capability indicating a supported time for determining timeoffsets based on DMRS sequences.
 9. The apparatus of claim 8, whereinthe capability is indicated for at least one of a number of controlchannel candidates, a number of time offset or time domain resourceassignment (TDRA) value hypotheses, or a subcarrier spacing.
 10. Theapparatus of claim 8, wherein the one or more processors are furtherconfigured to: receive an indication that the time offset is not lessthan the supported time; and determine, based at least in part on thesequence of the DMRS, the time offset based at least in part onreceiving the indication.
 11. An apparatus for wireless communication,comprising: a transceiver; a memory configured to store instructions;and one or more processors coupled with the memory and the transceiver,wherein the one or more processors are configured to: generate ademodulation reference signal (DMRS) that can be used to perform channelestimation for a downlink control channel to have a DMRS sequenceindicating a time offset from the downlink control channel to a downlinkdata channel, wherein the one or more processors are configured togenerate the DMRS at least in part by determining the DMRS sequence thatmaps to the time offset; transmit the downlink control channel and theDMRS; and transmit, based on the time offset, the downlink data channelafter the downlink control channel.
 12. The apparatus of claim 11,wherein the one or more processors are configured to generate the DMRSat least in part by determining the DMRS sequence that maps to a subsetof allowed time offsets that includes the time offset.
 13. The apparatusof claim 12, wherein the one or more processors are further configuredto transmit a configuration indicating the allowed time offsets.
 14. Theapparatus of claim 11, wherein the one or more processors are configuredto generate the DMRS at least in part by determining the DMRS sequencethat maps to a time domain resource assignment (TDRA) value related tothe time offset.
 15. The apparatus of claim 11, wherein the one or moreprocessors are configured to generate the DMRS at least in part bydetermining the DMRS sequence that maps to a subset of allowed timedomain resource assignment (TDRA) values that includes a TDRA valuerelated to the time offset.
 16. The apparatus of claim 15, wherein theone or more processors are further configured to transmit aconfiguration indicating the allowed TDRA values.
 17. The apparatus ofclaim 11, wherein the one or more processors are further configured toreceive a capability indicating a supported time for determining timeoffsets based on DMRS sequences, wherein the one or more processors areconfigured to generate the DMRS at least in part by selecting a DMRSsequence based on determining that the time offset is within thesupported time.
 18. The apparatus of claim 17, wherein the capability isindicated for at least one of a number of control channel candidates, anumber of time offset or time domain resource assignment (TDRA) valuehypotheses, or a subcarrier spacing.
 19. The apparatus of claim 17,wherein the one or more processors are further configured to transmit anindication that the time offset is not less than the supported time. 20.A method for wireless communication, comprising: receiving ademodulation reference signal (DMRS) that can be used to perform channelestimation for a downlink control channel, wherein a sequence of theDMRS indicates a time offset from the downlink control channel to adownlink data channel; buffering, based on receiving the DMRS and untila time at which the time offset is determined from the sequence of theDMRS, samples of the downlink data channel associated with the downlinkcontrol channel; flushing buffered samples of the downlink data channelwhere the time offset from the downlink control channel is after thetime at which the time offset is determined from the sequence of theDMRS; and processing at least a portion of the buffered samples of thedownlink data channel where the time offset from the downlink controlchannel is before the time at which the time offset is determined fromthe sequence of the DMRS.
 21. The method of claim 20, further comprisingdetermining the time offset based on a mapping between the sequence ofthe DMRS and the time offset.
 22. The method of claim 20, furthercomprising determining the time offset based on a mapping between thesequence of the DMRS and a subset of allowed time offsets.
 23. Themethod of claim 20, further comprising determining the time offset basedon a mapping between the sequence of the DMRS and a time domain resourceassignment (TDRA) value, and further comprising determining, from alookup table, the time offset based at least in part on a TDRA timeoffset value indicated for the TDRA value.
 24. The method of claim 20,further comprising: receiving a configuration indicating allowed timedomain resource assignment (TDRA) values; and determining the timeoffset based on a mapping between the sequence of the DMRS and a subsetof the allowed TDRA values.
 25. The method of claim 20, furthercomprising: transmitting a capability indicating a supported time fordetermining time offsets based on DMRS sequences; receiving anindication that the time offset is not less than the supported time; anddetermining, based at least in part on the sequence of the DMRS, thetime offset based at least in part on receiving the indication.
 26. Amethod for wireless communication, comprising: generating a demodulationreference signal (DMRS) that can be used to perform channel estimationfor a downlink control channel to have a DMRS sequence indicating a timeoffset from the downlink control channel to a downlink data channel,wherein generating the DMRS includes determining the DMRS sequence thatmaps to the time offset; transmitting the downlink control channel andthe DMRS; and transmitting, based on the time offset, the downlink datachannel after the downlink control channel.